232 research outputs found
A dual 2D model for the Quantum Hall Fluid
We present a dual two dimensional model for the Quantum Hall Fluid depending
on two parameters and show that this model has topologically non-trivial vacua
which are infrared stable fixed points of the Renormalization Group. The model
has a discrete (modular) symmetry which reproduces the fenomenological law of
corresponding states and allows for an unified description of the critical
points corresponding to Hall plateaus in terms of a 2 dimensional Conformal
Field Theory.Comment: 10 pages, Revtex, no figure
A CFT description of the BTZ black hole: topology versus geometry (or thermodynamics versus statistical mechanics
In this paper we review the properties of the black hole entropy in the light
of a general conformal field theory treatment. We find that the properties of
horizons of the BTZ black holes in ADS_{3}, can be described in terms of an
effective unitary CFT_{2} with central charge c=1 realized in terms of the
Fubini-Veneziano vertex operators.
It is found a relationship between the topological properties of the black
hole solution and the infinite algebra extension of the conformal group in 2D,
SU(2,2), i.e. the Virasoro Algebra, and its subgroup SL(2,Z) which generates
the modular symmetry. Such a symmetry induces a duality for the black hole
solution with angular momentum J\neq 0. On the light of such a global symmetry
we reanalyze the Cardy formula for CFT_{2} and its possible generalization to
D>2 proposed by E. Verlinde.Comment: 21 page
Black Hole in ADS and Quantum Field Theory
I will present a short review of recent achievements in understanding the
origin of the statistical properties versus the thermodynamical ones for Anti
De Sitter space--time, ADS from the point of view of the "dual" field
theory defined on the boundary of ADS conformal invariant, CFT.
We try to convince the audience that the symmetries of Quantum Field Theory
at the critical points are, on one side, at the basis of the thermodynamical
properties of Black Hole solution, i.e. the Hawking temperature and the
entropy ; on the other side the CFT in Euclidean time determines the
statistical properties of BH.Comment: Talk given at APC Meeting | Paris, 10-19 December, 200
Paired states on a torus
We analyze the modular properties of the effective CFT description for paired
states, proposed in cond-mat/0003453, corresponding to the non-standard filling
nu =1/(p+1). We construct its characters for the twisted and the untwisted
sector and the diagonal partition function. We show that the degrees of freedom
entering our partition function naturally go to complete a Z_2-orbifold
construction of the CFT for the Halperin state. Different behaviours for the p
even and p odd cases are also studied. Finally it is shown that the tunneling
phenomenon selects out a twist invariant CFT which is identified with the
Moore-Read model.Comment: 24 pages, 1 figure, Late
The Cardy-Verlinde equation in a spherical symmetric gravitational collapse
The Cardy-Verlinde formula is analyzed in the contest of the gravitational
collapse. Starting from the holographic principle, we show how the equations
for a homogeneous and isotropic gravitational collapse describe the formation
of the black hole entropy. Some comments on the role of the entangled entropy
and the connection with the c-theorem are made
Tunnelling Effects in a Brane System and Quantum Hall Physics
We argue that a system of interacting D-branes, generalizing a recent
proposal, can be modelled as a Quantum Hall fluid. We show that tachyon
condensation in such a system is equivalent to one particle tunnelling. In a
conformal field theory effective description, that induces a transition from a
theory with central charge c=2 to a theory with c=3/2, with a corresponding
symmetry enhancement.Comment: 12 pages, no figures, Latex, some aspects clarified, sect.3 expanded,
references adde
A conformal field theory description of the paired and parafermionic states in the quantum Hall effect
We extend the construction of the effective conformal field theory for the
Jain hierarchical fillings proposed in cond-mat/9912287 to the description of a
quantum Hall fluid at non standard fillings nu=m/(pm+2). The chiral primary
fields are found by using a procedure which induces twisted boundary conditions
on the m scalar fields; they appear as composite operators of a charged and
neutral component. The neutral modes describe parafermions and contribute to
the ground state wave function with a generalized Pfaffian term. Correlators of
Ne electrons in the presence of quasi-hole excitations are explicitly given for
m=2.Comment: 11 pages, plain Late
Migratory Dermatographic Urticaria Following COVID-19 Vaccine Booster in Young Adult Male
With the recent approval of booster vaccinations in the United States for adults who already received their primary vaccinations, millions of adults have been administered the Pfizer-BioNTech or Moderna booster vaccines.
Adverse events related to these vaccines continue to be reported and are majority self-limited. In this case report, we present a young male who acquired chronic, migratory dermatographic urticaria two weeks after administration of the Moderna mRNA-1273 COVID-19 vaccine booster
A twisted conformal field theory description of the Quantum Hall Effect
We construct an effective conformal field theory by using a procedure which
induces twisted boundary conditions for the fundamental scalar fields. That
allows to describe a quantum Hall fluid at Jain hierarchical filling,
nu=m/(2pm+1), in terms of one charged scalar field and m-1 neutral ones. Then
the resulting algebra of the chiral primary fields is U(1)xW_m. Finally the
ground state wave functions are given as correlators of appropriate composite
fields (a-electrons).Comment: 11 pages, plain Late
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